Peptide encoding and dual-function sRNAs in Bacillus subtilis

枯草芽孢杆菌是最重要的非致病性革兰氏阳性模式生物，它能向生长培养基中大量分泌蛋白质，因此被用于许多酶的工业生产，如淀粉酶和蛋白酶。与革兰氏阴性模式生物大肠杆菌相反，枯草芽孢杆菌具有天然的能力，可以在营养压力下产生孢子以在极端条件下生存。此外，由于它与炭疽芽胞杆菌或蜡样芽胞杆菌等致病性杆菌有关，因此它也可以作为调节这些致病性细菌代谢反应或应激的模式生物。本项目的主要目的是在枯草芽孢杆菌中鉴定新的肽编码和双功能sRNAs，并进一步从其表达、靶点和生物学作用方面对其进行表征。我们期望发现由短mrna或新的双功能sRNAs编码的小肽的新功能。实验工作将分为以下三个部分：1)分析四种肽编码sRNAs在不同生长和胁迫条件下的表达谱及表达调控。鉴定潜在的转录调节因子。2)使用C和n端标记肽的共洗脱和共免疫沉淀试验以及野生型，敲除和过表达菌株的转录组学和肽组学来寻找肽靶点。阐明这些肽的生物学作用。3)利用转录组学和体外和体内结合技术研究这些spRNAs的其他碱基配对功能

Bacillus subtilis is the most important non-pathogenic Gram-positive model organism that can secrete proteins in large quantities into the growth medium and is, therefore, used for the industrial production of a number of enzymes such as amylases and proteases. In contrast to the Gram- negative model organism E. coli, B. subtilis is naturally competent and can sporulate in response to nutritional stress to survive extreme conditions. Moreover, since it is related to pathogenic Bacilli as e.g. B. anthracis or B. cereus, it can be used as a model organism for the regulation of metabolic responses or stress of such pathogenic bacteria as well.The major aims of this project are to identify novel peptide encoding and dual-function sRNAs in B. subtilis and to further characterize them in terms of their expression, targets and biological role. We expect to discover novel functions for small peptides encoded by either short mRNAs or new dual function sRNAs.The experimental work will be divided into the following three parts:1) Analysis of expression profiles and expression control of four peptide encoding sRNAs under different growth and stress conditions. Identification of potential transcriptional regulators.2) Search for peptide targets using co-elution and co-immunoprecipitation assays with C- and N-terminally tagged peptides and transcriptomics and peptidomics with wild-type, knockout- and overexpression strains. Elucidation of the biological role of these peptides. 3) Investigation of additional base-pairing functions of these spRNAs using transcriptomics and a combination of in vitro and in vivo techniques